Connector assembly

Abstract: A connector assembly for printed circuit boards comprises a first connector part and a second connector part. The first connector part has a first housing of insulating material comprising a bottom and two opposite side walls and male contact elements mounted in the bottom of the housing arranged in rows and columns. The second connector part has a second housing of insulating material adapted to be inserted into the first housing with an insertion side and female contact elements mounted in the housing arranged in a corresponding manner in rows and columns. A ground contact plate is provided at both sides of each at least one column of female contact elements, wherein the ground contact plates at the insertion side of the second housing are projecting out of said housing along a distance substantially corresponding with the thickness of the bottom of the first housing. Slots are provided in the bottom of the first housing for receiving the ground contact plates.

Description: The invention relates to a connector assembly for printed circuit boards, comprising a first connector part with a first housing of insulating material and having a bottom and two opposite side walls and with male contact elements mounted in the bottom of the housing and arranged in rows and columns and a second connector part with a second housing of insulating material and adapted to be inserted into the first housing with an insertion side and with female contact elements mounted in the housing and arranged in a corresponding manner in rows and columns. Such a connector assembly is disclosed for example in EP-A-0 446 980. In this known connector assembly the second connector part comprises a plurality of outer conductors each substantially enclosing in circumferential direction at least one female contact element operating as signal contact and each contacting the adjacent ground contacts of the corresponding signal contact of the first connector part. In this manner a correct signal transmission can be obtained also at high bit rates of the signals to be transmitted. Further, outer conductors can also be provided in this known connector assembly for the male contact elements operating as signal contacts. Although an optimal signal transmission can be realized with this known connector assembly also at high bit rates, the construction is less suitable for applications, wherein the signal contacts must be very closely spaced one from the other. The invention aims to provide a connector assembly of the abovementioned type, wherein an optimal signal transmission at high bit rates is possible and wherein the signal contacts can be closely spaced and the construction can be simplified. To this end the connector assembly according to the invention is characterized in that a ground contact plate is provided at both sides of each at least one column of female contact elements, wherein the ground contact plates at the insertion side of the second housing are projecting out of said housing along a distance substantially corresponding with the thickness of the bottom of the first housing, and in that slots are provided in the bottom of the first housing for receiving the ground contact plates. In this manner a connector assembly is obtained, wherein the second connector part is provided with ground contact plates operating in the coupled position of the connector assembly as a shielding for the columns of contact elements in both connector parts. By means of a suitable choice of signal and ground contact elements in each column it is possible in this manner to realize an optimal operation with a relatively simple construction. According to a favourable embodiment of the connector assembly of the invention each column comprises at least two pairs of signal contact elements being separated by a ground contact element, wherein the intermediate distance between successive columns of contact elements is preferably 2 mm. In this manner a connector assembly is obtained, wherein a differential pair of signal contacts is available per mm. The invention will be further explained with reference to the drawings, in which some embodiments of the connector assembly according to the invention are shown. Fig. 1 is a side view, partially in cross section and partially broken away, of a first embodiment of the connector assembly according to the invention in the coupled position. Fig. 2 is a cross section of the first connector part of the connector assembly of Fig. 1. Fig. 3 is a top view of the first housing of the first connector part of Fig. 2. Fig. 4 is a side view, partially in cross section and partially broken away, of a second embodiment of the connector assembly according to the invention in the coupled position. Fig. 5 is a perspective and partially exploded view of the second connector part of the connector assembly of Fig. 4. Fig. 6 is a cross section corresponding with Fig. 2 and showing an alternative embodiment of the first connector part. Fig. 7 is a side view, partially in cross section and partially broken away, of a third embodiment of the connector assembly according to the invention in the coupled position. Fig. 8 is a cross section of the first connector part of the connector assembly of Fig. 7. Fig. 9 is a perspective view, partially exploded and partially broken away, of an alternative embodiment of the first connector part of the connector assembly according to the invention. Fig. 1 shows a side view, partially in cross section and partially exploded, of a connector assembly 1 for connecting a printed circuit board 2 to a printed circuit board 3 generally indicated as back panel. A first connector part 4, shown in cross section in Fig. 2, is mounted on the printed circuit board 3. The connector part 4 comprises a housing 5 of insulating material, a top view of which is shown in Fig. 3, with a bottom 6 and two opposite side walls 7 and 8, respectively. In the bottom 6 openings 9 are formed, in which contact pins 10 operating as male contact elements are fixed. The contact pins 10 are arranged in rows and columns, wherein in the embodiment shown six columns each having five contact pins 10 are provided. According to the cross section of Fig. 2 and the top view of Fig. 3, respectively, each column of contact pins includes four signal contact pins being divided into two pairs by a central ground contact pin. the distance between the contact pins 10 in row direction is 2 mm in the embodiment shown, so that one pair of signal contacts is provided per mm. In this manner each pair of signal contact pins can transmit one pair of different signals. If desired it is also possible to apply a higher number of rows and columns of contact pins 10. It is further possible that the columns of contact pins comprise alternatingly a signal contact pin and a ground contact pin, other arrangements of signal and ground contact pins or even signal contact pins only. The connector assembly 1 further comprises a second connector part 11 with a second housing 12 of insulating material. This second housing 12 is inserted into the first housing 5 with an insertion side 13. Female contact elements 14 arranged in the same manner as the contact pins 10 are mounted in the second housing 12, said contact elements engaging the contact pins 10 in the inserted position of Fig. 1 in a manner known per se. As appears from the cross-sections of Figs. 1 and 2, both the contact pins 10 and the female contact elements 14 are provided with portions 15 and 16, respectively, being fixed in so-called plated through holes of the printed circuit boards 3 and 2, respectively, by insertion. The second connector part 11 comprises a ground contact plate 17 on both sides of each column of female contact elements 14, said ground contact plates 17 projecting out of the housing 12 at the insertion side 13 along a distance substantially corresponding with the thickness of the bottom 6 of the housing 5. For receiving these projecting parts of the ground contact plates 17 the bottom 6 of the housing 5 is provided with slots 18. In this manner it is obtained that the shielding of each column of contact elements 14 of the second connector part 11 also forms a shielding between the columns of contact pins 10 of the first connector part 4 in the coupled position of the connector assembly 1. The ground contact plates 17 can include suitable contact elements at the edge directed towards the printed circuit board 2, said contact elements contacting for example a ground contact conductor layer at the surface of the printed circuit board 2. These contact elements are indicated in Fig. 5 by reference numeral 17'. Of course, it is also possible to provide the ground contact plates 17 with insertion contact portions. The first connector part 4 comprises shielding plates 19 mounted on the side walls 7, 8 of the first housing 5. These shielding plates 19 are provided with contact springs 20 projecting into the housing 5 through openings 21 in the side walls 7, 8. Further, the shielding plates 19 have contact areas 22 contacting a suitable conductor on the surface of the printed circuit board 3. In the embodiment shown in Fig. 1, the shielding plates 19 further include contact springs 23 projecting into the slots 18 of the housing 5 and contacting the ground contact plates 17 in the coupled position of the connector assembly 1. The contact springs 20 of the shielding plate 19 on the side wall 8 are contacting the edges of the ground contact plates 17. The connector part 11 further comprises a shielding plate 24 being mainly L-shaped, wherein the short leg extends along the back side of the housing 12 and the long leg extends along the upper side of the housing. The short leg of the shielding plate 24 includes contact parts 25 inserted into openings of the printed circuit board 2 and contacting a corresponding conductor of the printed circuit board 2. In the inserted position of Fig. 1, the contact springs 20 of the shielding plate 19 of the side wall 7 are contacting the shielding plate 24. It is possible to provide the ground contact plates 17 and/or the shielding plate 24 of suitable contact means ensuring a good connection between the shielding plate 24 and the ground contact plates 17. As an alternative the ground contact plates 17 and the shielding plate 24 cannot be in contact with each other with the exception of a contact between the shielding plate 24 and an extension 26 of each ground contact plate 17. As shown in fig. 1, the extensions 26 project at the back side out of the housing 12 and project through slots in the short leg of shielding plate 24, not visible in Fig. 1, where the extensions 26 contact the shielding plate 24. As appears from Figs. 2 and 3, the parts 27 of the bottom 6 between the slots 18 are mutually connected by a web 28 to strengthen the bottom 6. Fig. 4 shows a connector assembly 29 being mainly made in the same manner as the connector assembly 1 of Fig. 1. Corresponding parts are indicated with the same reference numerals. In the connector assembly 1 of Fig. 1 the contact springs 20 of the shielding plate 19 at the side wall 8 of the housing 5 are contacting the edges of the ground contact plates 17, wherein for a good long term operation a special machining of these edges of the ground contact plates 17 would be desirable. In the connector assembly 29 a contact between the edges of the ground contact plates 17 and the contact springs 20 is obviated by means of a connection plate 30 with arcuate contact means 31, said connection plate 30 being attached at the lower side of the connector part 11. These arcuate contact means 31 are contacting the contact springs 20 of the shielding plate 19 in the coupled position of the connector assembly 29. The connection plate 30 in its position mounted on the printed circuit board 2, is connected with a corresponding conductor of the printed circuit board 2 and is also contacting the ground contact plates 17. The connector part 11 of the connector assembly 29 is shown in a perspective view in Fig. 5, wherein the shielding plate 19 and the connection plate 30 are shown separated from the housing 12. Fig. 5 shows that the connection plate 30 is provided with contact elements 32 ensuring a good connection with a conductor on the surface of the printed circuit board 2. Further, the connection plate 30 includes openings 33 for the attachment of the connection plate on the housing 12 by means of lugs 34, only one of which being visible in Fig. 5. It can further be seen in Fig. 5 that the shielding plate 24 has slots 35 for the extensions 26 of the ground contact plates 17 in the part on the back side of the housing 12. On both sides of each slot 35 there is a contact lip 36 engaging the extension 26. At the upper side of the housing 12 two positioning lugs 37 are provided co-operating with slots 38 in the side wall 7 of the housing 5 of the first connector part 4, so that the connector part 11 can be inserted into the connector part 4 in one position only. The shielding plate 24 has two slots 39, in which the lugs 37 are received. Lips 40 are formed for engaging under a protruting part of the lugs 37 to hold the shielding plate 24 on the housing 12. It is noted that the ground contact plates 7 are mounted in the housing 12 during injection moulding. The ground contact plates 17 are supported in the mould for making the housing 12 and are provided with openings 41, 42 filled with the insulating material of the housing 12, whereby the ground contact plates 17 are anchored well in the housing 12. As shown in Figs. 3 and 5, the outer slots 18 and ground contact plates 17, respectively, have a dimension and row direction, which is half of the corresponding dimension of the remaining slots 18 and ground contact plates 17. In this manner a plurality of connector parts 4 and 11, respectively, can be located one next to the other, wherein the distance between the successive columns of contact pins 10 and contact elements 14 is maintained also in case of two connector parts located one next to the other. Fig. 6 shows a cross section of a first connector part 43 being mainly made in the same manner as the connector part 4. Corresponding parts are indicated with the same reference numerals. In this case the shielding plates 19 are provided with further contact tongues 44 connected with a conductor of the printed circuit board 3 by soldering or another suitable connecting technique. In the embodiments of the connector assembly according to the invention as shown in Figs. 1-6, the ground contact plates 17 are connected with the shielding plates 19, 24. For certain applications it can be desirable to make no connection between the shielding and the ground contact plates. Fig. 7 shows a connector assembly 45, wherein a separation is established between the shielding and the ground contact plates. For the remaining part this embodiment corresponds with the above described embodiments, wherein corresponding parts are indicated with the same reference numerals. Fig. 8 shows the first connector part 4 of the connector assembly 45 in cross section. In this case the first connector part 4 is provided with a contact spring element 46 in each slot 18 in the bottom 6, said contact spring element 46 being connected with a ground conductor of the printed circuit board 3 by means of a contact pin 47. The contact pins 47 are aligned with the row of ground contact pins 10. In the inserted position these contact springs 46 are contacting the ground contact plates 48 being mainly made in the same manner as the ground contact plates 17. Also in this case the ground contact plates 48 are projecting out of the housing at the insertion side 13 of the housing 12 and are received in the slots 18 of the bottom 6 of the housing 5 in the coupled position of the connector assembly 45. The ground contact plates 48 are, however, shorter than the ground contact plates 17 so that they do not contact the shielding plate 24 of the second connector part 11. Further, the shielding plates 19 of the first connector part 4 are in this case of course made without the contact springs 23. The shielding plates 19 have contact tongues 49 which are connected with a shielding conductor of the printed circuit board 3. Of course, the connection plate 30 of the second connector part 11 is not contacting the ground contact plates 48 in this case. Fig. 9 shows a perspective view of a first connector part 50 being mainly made in the same manner as the first connector parts 4 and 43, respectively. Corresponding parts are indicated by the same reference numerals. In this case the connector part 50 is provided with a ground contact unit 51 having two ground contact plates 52 for each slot 18 in the bottom 6 of the housing 5, which ground contact plates 52 are received in a recess 53 adjacent to the corresponding slot 18. Each ground contact plate 52 includes a contact spring 53 projecting into the corresponding slot 18 and contacting the corresponding ground contact plate 17 in the coupled position of the connector assembly. Each ground contact plate 52 has mainly a H-shape wherein the legs of the H-shape are aligned with the rows of signal contact pins 10. In the embodiment of Fig. 9 the ground contact unit 51 is unitary with the shielding plates 19 so that when using the connector part 50 a connection is made between the ground contact plates 17 and the shielding plates 19, 24. If a separation is desired between shielding and grounding, it is possible to keep the ground contact unit 51 separated from the shielding plates 19, wherein in that case the ground contact unit 51 is provided with one or more suitable ground contact means. The application of the ground contact unit 51 has the advantage that in a restricted decoupled position caused by tolerances in the mounting system, in which the connector assembly and the corresponding printed circuit boards are accommodated, an optimal ground shielding is guaranteed between the columns of contact pins 10. Moreover, a good long term connection between the ground contact unit 51 and the ground contact plates 17 is guaranteed by the contact springs 54 engaging the surface of the ground contact plates 17. It is noted that only one contact pin 10 is shown in Fig. 9 for illustration purposes. However, it will be clear that all openings 9 in the bottom 6 of the housing 5 are provided with contact pins 10. Although in the above described embodiments a ground contact plate is provided at each side of each column of female contact elements, it is also possible that more than one column of contact elements is provided between each two ground contact plates. It is noted that the contact pins 10 each are provided with a shoulder 80 projecting at both sides of the contact pin, an upper surface of which can be seen in Fig. 9. Because the contact pins 10 in the described contact assemblies are mounted at a pitch of only 2 mm and the slots 18 are provided between the columns of contact pins, it is not possible to mount the contact pins 10 with their shoulders aligned with the row direction as usual up till now. In the described connector assemblies the shoulders 80 are directed into column direction as shown in Figs. 3, 9. Thereby the contact surfaces 81 of the contact pin parts 82 projecting into the housing, which are extending parallel to the shoulders 80 in the conventional contact pins, would also extend into column direction. At the application of the usual female contact elements, these female contact elements would not co-operate anymore with the contact surfaces 81 of the contact pins 10. In the connector assembly according to the invention contact pins are therefore used in the first connector part having a contact pin part 82 twisted along 90° with respect to the remaining contact pin part. In this manner it is obtained that the contact surfaces 81 extend in row direction so that they are contacting the female contact elements in the correct manner. A suitable method for manufacturing the contact pins with a twisted contact pin part is described in a patent application of the applicant of the same date. Although the invention is explained above with reference to an application as connector assembly for printed circuit boards, the invention can also be applied in case of other types of connector assemblies, e.g. a cable connector. The invention is not restricted to the above described embodiments, which can be varied in a number of ways within the scope of the claims.

Claims: Connector assembly (1,29), comprising a first connector part (4,43) with a first housing (5) of insulating material and having a bottom (6) and two opposite side walls (7,8) and with male contact elements (10) mounted in the bottom of the housing and arranged in rows and columns, and a second connector part (11) with a second housing (12) of insulating material and adapted to be inserted into the first housing with an insertion side (13) and with female contact elements (14) mounted in the housing and arranged in a corresponding manner in rows and columns, characterized in that a ground contact plate (17) is provided at both sides of each at least one column of female contact elements (14), wherein the ground contact plates at the insertion side (13) of the second housing (12) are projecting out of said housing along a distance corresponding with the thickness of the bottom (6) of the first housing (5), and in that slots (18) are provided in the bottom (6) of the first housing (5) for receiving the ground contact plates (17). Connector assembly according to claim 1, characterized in that each column comprises at least two pairs of signal contact elements separated by a ground contact element, wherein the intermediate distance between successive columns of contact elements is preferably 2 mm. Connector assembly according to claim 1 or 2, characterized in that each ground contact plate (17) has contact means (17') projecting at the lower side of the second housing (12) and adapted to be connected to a conductor of a printed circuit board (2). Connector assembly according to claim 1, 2 or 3, characterized in that the first housing (5) comprises shielding plates (19) provided on the side walls (7,8), said shielding plates being provided with contact means (22,44) adapted to be connected to a conductor of a printed circuit board (3) and with contact spring means (20) projecting into the housing (5) through openings (21) in the side walls (7,8). Connector assembly according to claim 4, characterized in that the second housing (12) comprises a shielding plate (24) extending along the upper side and the back side of the housing opposite of the insertion side (13) and having contact means (25) adapted to be connected to a conductor of a printed circuit board (2), said shielding plate contacting the contact spring means (20) of the corresponding shielding plate (19) of the first housing (5) when the assembly is coupled. Connector assembly according to claim 5, characterized in that the contact spring means (20) of the other shielding plate (19) of the first housing (5) are contacting one or more ground contact plates (17) of the second housing (12) when the assembly is coupled. Connector assembly according to claim 5, characterized in that the second housing (12) has a connection plate (30) with arcuate contact means (31) at the lower side, said connection plate adapted to be connected to a shielding conductor of a printed circuit board, wherein said arcuate contact means are contacting the contact spring means (20) of the adjacent shielding plate (19) of the first housing (5) when the assembly is coupled. Connector assembly according to anyone of claims 4-7, characterized in that each shielding plate (19) of the first housing (5) comprises contact spring strips (23), each of said contact spring strips projecting into a slot (18) in the bottom (6) of the housing for contacting a ground contact plate (17) of the second housing (12). Connector assembly according to anyone of claims 5-8, characterized in that the ground contact plates (17) and the shielding plate (24) of the second housing (12) are electrically interconnected. Connector assembly according to claim 9, characterized in that each ground contact plate (17) has an extension (26) projecting at the back side of the second housing (12) and in that the shielding plate (24) of the second housing has slots (35) for receiving the extensions of the ground contact plates. Connector assembly according to anyone of claims 5-10, characterized in that the second housing (12) comprises at its upper side at least one positioning lug (37) adapted to co-operate with a corresponding slot (38) in one (7) of the side walls of the first housing (5), wherein the shielding plate (24) of the second housing (12) has a slot (39) for each positioning lug (37) and means (40) are provided for holding the shielding plate (24) on the positioning lug(s). Connector assembly according to anyone of claims 4-11, characterized in that each shielding plate (19) of the first housing (5) comprises at least one contact area (22) for contacting a surface conductor of a printed circuit board (3) to be mounted under the bottom (6) of the housing and/or at least one contact tongue (44) for connection to a surface conductor of a printed circuit board next to the bottom of the housing. Connector assembly according to anyone of the preceding claims, characterized in that the bottom (6) of the first housing (5) comprises bottom parts (27) separated by the slots (18), wherein the bottom parts (27) are interconnected preferably at the centre.

Inventors: JONCKHEERE LUC, MORLION DANNY, JONCKHEERE, LUC, MORLION, DANNY
Applicants: FRAMATOME CONNECTORS INT, FRAMATOME CONNECTORS INTERNATIONAL
Application year: 1994
Main classification: H01R23
IPC codes: H01R24, H01R13, H01R12